From The Editor | August 29, 2017

4 Steps For Controlling Water Loss At Small Utilities

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By Kevin Westerling
@KevinOnWater

4 Steps For Controlling Water Loss At Small Utilities

The bigger water utilities have the resources, but small utilities face many of the same problems — namely failing pipeline infrastructure and water loss. So what are the solutions and best practices within small utilities’ grasp? One small utility shared its successful approach to controlling water loss as guidance for those with similar struggles.

Rocky View Water Co-op Ltd., a member-owned co-operative in Calgary, AB, knew it had a non-revenue water problem back in 2014. One-third of their distribution mains were near the end of their service life, many featuring 20-year-old plastic fittings and bell-and-spigot joints that are prone to leaks. When they did the math (annual consumption divided by distribution total), they discovered that their water loss rate was 39 percent. It was time to implement an official Water Loss Control Program.

But in contrast to large utilities with lots of customers and staff, small utilities must maintain an expansive distribution system with understaffed operations and relatively few ratepayers to support investment. The key to getting a handle — or even getting started — on water loss, according Brad Mason, general manager at Rocky View Water, was the creation of a “policy document” that outlines a coherent and standardized approach to the issue.

Mason shared the basic tenets of his co-op’s policy document, along with some lessons learned in carrying out their Water Loss Control Program, during a session at ACE17, the annual conference conducted by AWWA. It is driven by four simple steps:

  1. Water Audit
  2. Intervention
  3. Evaluation
  4. Repeat

Water Audit

Mason recommended that utilities consult the U.S. EPA’s “Control and Mitigation of Drinking Water Losses in Distribution Systems” for guidance in conducting the audit, as well as AWWA’s “Water Audits and Loss Control Programs” manual (M36). The latter, which goes into detail on water balance as an auditing technique, is a reference tool that Mason admitted “in hindsight, we should have used more than we did” to lessen the learning curve the co-op endured in understanding the IWA/AWWA Water Audit Method.

Ultimately, Rocky View Water’s concerns about the condition of their water mains were confirmed. In fact, leaks were worse than they had thought — and their losses a bit different than they figured based on a “top down” audit conducted in 2014. The 2015 audit, using the water balance approach and aided by better data, revealed that apparent losses were less, while real losses were greater.

Intervention/Evaluation

A number of programmatic and technology interventions were applied and their efficacy evaluated, including:

  • Active leak detection — Step testing was conducted and new acoustic leak detection equipment was purchased, both producing excellent leak-finding results (along with flow monitoring and visual inspection).
  • Pressure management — Installation of real-time pressure monitoring stations by district metered area (DMA), with web-based reporting and alarm notifications via email.
  • Asset management — Asset management software was purchased and, for the first time, assets were identified and recorded. Risk analysis was conducted, with high-risk distribution mains designated for priority replacement. The software enables long-term capital planning and validates capital funding requirement and ratesetting. It also includes modules for maintenance, work orders, inventory, staff training, etc.
  • Production flow meter testing — Discovered issues related to meter size (current flow vs. peak capacity) and flow volumes resulting in “significant” margins of error.
  • Customer meter replacement — Results of post-removal meter testing showed under-reading of 15 to 30 percent on “most meters,” while the highest under-reading was 78 percent. This resulted in accelerated meter replacement program with automatic meter reading (AMR) featuring data-logging capability, “leak flags,” and customer notifications.
  • Increasing the speed and quality of repairs — Focus on Awareness, Location, and Repair (ALR) times:
    • Awareness time …to become aware that a leak exists;
    • Location time …to pinpoint the source; and
    • Repair time …to halt the leakage.
  • Administrative review — Past record-keeping and process errors were uncovered, as were customers who had active accounts with no meters or non-functioning meters. One homeowner was living without a meter for seven years.

Rocky View Water plans to continue down the path of an Asset Management Program and has a number of pending interventions on the horizon, including main replacement, service line replacement, and increased use of online pressure monitoring.

Also planned for the future are more water audits, interventions, and evaluations (hence “Repeat”).

For other small utilities ready to embark on their own journey to water loss control, Mason shared what he learned from his organization’s trials, tribulations, and ultimate success.

  • Patience. It is a multi-year process, so don’t expect fast results.
  • Perseverance — for when the board asks “Why are we doing this?” and “Is this working?”
  • Don’t put too much faith in your first “top down” audit.
  • Don’t expect your second audit to be truly “bottom up.”
  • Producing valid data can be time-consuming.
  • As a small system, there is great value in conducting the Water Audit; even if system resources are limited, you will at least learn the issues and what to prioritize.
  • Two years later, Rocky View Water is not getting reliable data from DMAs. Mason advised utilities to consider both pressure and flow, stating that “we should have looked at pressure zones first and flow zones second.”
  • Customer meter replacement is “worth every penny” and made a bigger difference that the co-op expected.

Mason called his policy document “a touchstone that should be used throughout the process” of creating a Water Loss Control Program. It is high level by design, as the specific details of a program will be different for every utility. “It reminds us of the why, not the what,” he said.

To his credit, it also teaches small utilities how.

Image credit: "Water Main Leak," Andrew E. Russell, 2013, used under an Attribution 2.0 Generic license: https://creativecommons.org/licenses/by/2.0/